mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-04 19:00:09 +00:00
92 lines
4.0 KiB
C
92 lines
4.0 KiB
C
/* Copyright (C) 1998, 2000 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
|
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
#ifndef _SYS_DEBUGREG_H
|
|
#define _SYS_DEBUGREG_H 1
|
|
|
|
/* Indicate the register numbers for a number of the specific
|
|
debug registers. Registers 0-3 contain the addresses we wish to trap on */
|
|
#define DR_FIRSTADDR 0 /* u_debugreg[DR_FIRSTADDR] */
|
|
#define DR_LASTADDR 3 /* u_debugreg[DR_LASTADDR] */
|
|
|
|
#define DR_STATUS 6 /* u_debugreg[DR_STATUS] */
|
|
#define DR_CONTROL 7 /* u_debugreg[DR_CONTROL] */
|
|
|
|
/* Define a few things for the status register. We can use this to determine
|
|
which debugging register was responsible for the trap. The other bits
|
|
are either reserved or not of interest to us. */
|
|
|
|
#define DR_TRAP0 (0x1) /* db0 */
|
|
#define DR_TRAP1 (0x2) /* db1 */
|
|
#define DR_TRAP2 (0x4) /* db2 */
|
|
#define DR_TRAP3 (0x8) /* db3 */
|
|
|
|
#define DR_STEP (0x4000) /* single-step */
|
|
#define DR_SWITCH (0x8000) /* task switch */
|
|
|
|
/* Now define a bunch of things for manipulating the control register.
|
|
The top two bytes of the control register consist of 4 fields of 4
|
|
bits - each field corresponds to one of the four debug registers,
|
|
and indicates what types of access we trap on, and how large the data
|
|
field is that we are looking at */
|
|
|
|
#define DR_CONTROL_SHIFT 16 /* Skip this many bits in ctl register */
|
|
#define DR_CONTROL_SIZE 4 /* 4 control bits per register */
|
|
|
|
#define DR_RW_EXECUTE (0x0) /* Settings for the access types to trap on */
|
|
#define DR_RW_WRITE (0x1)
|
|
#define DR_RW_READ (0x3)
|
|
|
|
#define DR_LEN_1 (0x0) /* Settings for data length to trap on */
|
|
#define DR_LEN_2 (0x4)
|
|
#define DR_LEN_4 (0xC)
|
|
|
|
/* The low byte to the control register determine which registers are
|
|
enabled. There are 4 fields of two bits. One bit is "local", meaning
|
|
that the processor will reset the bit after a task switch and the other
|
|
is global meaning that we have to explicitly reset the bit. With linux,
|
|
you can use either one, since we explicitly zero the register when we enter
|
|
kernel mode. */
|
|
|
|
#define DR_LOCAL_ENABLE_SHIFT 0 /* Extra shift to the local enable bit */
|
|
#define DR_GLOBAL_ENABLE_SHIFT 1 /* Extra shift to the global enable bit */
|
|
#define DR_ENABLE_SIZE 2 /* 2 enable bits per register */
|
|
|
|
#define DR_LOCAL_ENABLE_MASK (0x55) /* Set local bits for all 4 regs */
|
|
#define DR_GLOBAL_ENABLE_MASK (0xAA) /* Set global bits for all 4 regs */
|
|
|
|
/* The second byte to the control register has a few special things.
|
|
|
|
On the i386, you should set the DR_LOCAL_SLOWDOWN or
|
|
DR_GLOBAL_SLOWDOWN bits if you want to know exactly which
|
|
instruction triggered the watchpoint. Setting these bits causes
|
|
the processor to run more slowly, but leaving them clear makes it
|
|
treat watchpoint hits as imprecise exceptions, so you can't
|
|
reliably determine which instruction caused the hit.
|
|
|
|
The i486 and all later IA-32 processors ignore DR_LOCAL_SLOWDOWN
|
|
and DR_GLOBAL_SLOWDOWN. They always report the exception
|
|
precisely, except in some rare cases, which the user can't do
|
|
anything about. */
|
|
|
|
#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */
|
|
#define DR_LOCAL_SLOWDOWN (0x100) /* Local slow the pipeline */
|
|
#define DR_GLOBAL_SLOWDOWN (0x200) /* Global slow the pipeline */
|
|
|
|
#endif /* sys/debugreg.h */
|